| Wind is recycled energy source. Nowadays, the wind energy gains more and more recognition under the stress of energy and circumstance. The wind resource of our country is plenty, which has big potential to be used. To develop wind electricity and water electricity is a long-term energy source policy of our country.To build up a simulation model for wind turbine generator system is very important because of a lot of requirements, such as high dependability of electricity system. With the development of electricity operation system and morecomplicated control system, it is more important and necessary for testing the control system by a simulation model. Besides, simulation system can be a simulation "test" platform for the realization of control methods and adjustment of parameters. Therefore, the wind turbine generator system simulation model is built up in this thesis to simulate the operation characteristic and to judge if the parameters are reasonable. In a word, the dynamic simulation system is necessary for the design, manufacture, protection, measurement of wind turbine system.Now, there are two popular wind turbine generator systems: (1) Double-speed asynchronous wind turbine generator system. (2) Variable speed constant frequency (VSCF) double-fed generator system. The latter which can capture wind energy with the highest efficiency has good operation characteristic, but the former has simple and reliable structure. In this thesis, the two kinds of wind turbine generator systems are simulated.Firstly, in this thesis, a model of a true double speed cageasynchronous wind turbine generator is analyzed by ANSOFT/ RMxprt and ANSOFT / MAXWELL 2D software. The generator parameters are calculated and magnetic field is analyzed by the finite element method. The dynamic behavior of the generator is also simulated by ANSOFT / TRANSIENT. Furthermore, a new algorithm is proposed to calculate the parameters of the motor based on the results obtained by MAXWELL 2D static electromagnetic field analysis.Secondly, MATLAB / SIMULINK tool box is employed to construct the dynamic simulation modules for whole stall regulation wind turbine generator system so that the dynamic operation of the system may be simulated. The sample generator is a double-speed one with 4/6 poles. Different operating states of the wind turbine generator system are simulated, such as the switching process of the double-speed generator, the small generator "over-speeding", and the generator being short circuited and so on. All these simulation results are analyzed. By the analysis of the simulation results,the optimal wind speed range for switching to the small generator from the big one may be determined. The impacts of short circuited generator on the grid and on the generator itself are analyzed as well. A simulation model for the self-excited asynchronous generator, considering the saturation effects, is proposed, based on the library models of MATLAB /SIMULINK. Then, voltage variation curves corresponding to self-excited voltage setting up and rated loads cutting out abruptly are obtained respectively.Finally, the double-fed wind turbine generator system is simulated by MATLAB/SIMULINK. Flowing up the maximum wind energy, VSVF vector control is operated on the wind turbine generator when wind changes. In the simulation, both the magnitude and phase of stator current and voltage can be controlled by adjusting the rotor voltage, and the output power and power factor also can be adjusted. The analysis of the simulation results shows that the double-fed VSVF wind turbine generator has a good dynamic characteristic by thevector control.
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